Type-writing machine.



R. H. STROTHER. TYPE WRITING MACHINE. APPLICATION FILED MAB. 24, 1910.

Patented Aug. 23, 1910.

9 INVENTEIR m78 40; JMM

TTUR'NEYY R. H. STROTHER.

TYPE WRITING MACHINE.

APPLICATION FILED MAR. 24, 1910.

967,995. Patented Aug. 23, 1910.

3 SHEETS-411E111 2.

N w E WITNESEJEE: NVENTEIFL M JAM 96 4 E MM' H15 ATTORNEY R. H. STROTHER. TYPE WRITING MAGHINEL APPLICATION FILED 11.24, 1910.

967,995. Patented Aug. 23, 1910.

3 BHEBTS-SHEET 3 WITNEEIEEi INVENTEIFL f%. M Mm HIEATTUR'NEY UNITED STATES PATENT OFFICE.

ROBERT H. STROTHER, 0F MONTCLAIR, NEW JERSEY, ASSIGNOR TO UNION TYPE- WRITER COMPANY, OF ILION, NEW YORK, A CORPORATION OF NEW YORK.

TYPE-WRITING MACHINE.

Specification of Letters Patent.

Application filed March 24, 1310.

To all whom it may concern:

Be it known that I, Itonnn'r I-I. S'rim'rirnn, I

citizen of the United States, and resident of Montclair, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Type- VVriting Machines, of which the following is a specification.

My invention relates to typewriting machines and more particularly to the type actions of such machines.

The principal object of the invention is to provide improved devices for operating the type bars of a fr0nt-strike or similar typewriting machine, said devices including means which give a high leverage of a key on the corresponding type bar at the initial part of the key depression and said leverage diminishing as the key descends; in other words, to provide for a so-ealled accelerated motion of the type bar.

Another obj cot is to provide a sort of type action in Which thc'initial leverage and also the degree of acceleration can be made anything desired.

Another object is-to provide a series of type actions of the kind referred to, in which the action is uniform throughout the system, notwithstanding necessary dilferences in the lengths of the sub-levers and of the key levers.

Another object is to accomplish the ends above referred to by very simple and inexpensive means.

To the above and other ends my invention consists in certain features of construction and combinations and arrangements of parts, all of which will be fully set forth herein and particularly pointed out in the claims.

In the accompanying drawings, Figure 1 is a front to rear vertical sectional vlew of a typewriting machine having my invention embodied therein and with parts omitted. Fig. 2 is a plan view of the base portion of the machine, parts being omitted and parts broken away. Fig. 3 is a side elevation of two of the type actions, this figure being partly in the nature of 9. diagram to illustrate the principle of the invention.

My invention is applicable or adaptable to various styles of typewriting machines and for the sake of illustration I have here shown it embodied in amachine having some of the characteristics of a Monarch typewriter.

The machine shown comprises a base 1., corner posts 2 and a top plate 8 from which last rise standards t which support the sta tionary rails 5 of a carriage (3 in which there is mounted a platen 7. The carriage is shown supported by roller bearings 8 in a manner similar to the Monarch typewriter. The carriage is fed by a spring drum 10 and has pivotally mounted thereon a feed rack 11 meshing with a feed pinion 12 which controls an escapcment wheel 18 which, in turn, is controlled by feed dogs 14 mounted on a dog rocker 15 operated by a depending link 16. The type bars 17, each carrying two types, are pivoted in hangers 18 which are mounted on a segment 20 which segment has connected therewith a type rest 21. The type bars are shown provided with returning springs 22 like those of the Monarch machine, although such returning springs are not necessarily required in connection with the type bar operating mechanism shown. The printing keys 23 are mounted in the ordinary standard arrangement on the forward ends of a series of floating key levers 24:, the forward ends of which are or may be guided by a comb plate 25. In the presentinstance, the levers 24 converge back of said comb plate as shown in Fig. 2 so as to bring the rear ends of said levers into a compass of the same width as the system of type bars, though in other forms of the invention this is not necessary. Near its rear end each of the levers 24 is pivoted at 26 to an approximately horizontal link 27, said link, in the present instance, consisting of one arm of a bell crank sub-lever which also has an upright arm 28 which is connected with the corresponding type bar 17 by means of a forwardly directed link 30. The upstanding arms 28 of the sub-levers occupy substantially the same position as the corresponding arms of the sub-levers employed in the Monarch machine and, as here shown, the links 30 are so disposed as to allow the segment 20 to have an up and down case shift motion. The sub'levers 27, 28 are each pivoted at 31 to a hanger 32 consisting of a plate of sheet metal seated in a slot cut in the upper edge of a transverse frame bar 33. A cover-plate or bar 34 lies on top of all the hangers 32 and is secured in position by screws 35. These hangers are subjected to a pull toward the front of the machine and each of them is provided with 9. depending 33 so as to resist this pull.

key levers 24 extends downward and toward the rear forming a downwardly inclined branch 37 to which is pivoted at 38 a link 40 which extends from the point 38 outward and toward the front of the machine, its forward end being pivoted at 41 to a hanger 42 similar to the hangers 32 and similarly mounted in a cross bar 43 having a cover plate 44 secured thereto by screws 45. Neglecting for the moment the upper arm of the sub-lever each key lever is thus hung on two links 27 and 40 and it thereforeconstitutes a floating lever. The con struction is such that if one of the keys 23 be depressed the rear end of the corresponding lever will move upward as indicated in broken lines in Fig. 3, thus operating the corresponding type bar. From an inspection of said Fig. 3 and referring for the present to the key lever 24 that is nearest the observer in said figure, it will be noted that a line 46 has been drawn through the centers of the pivots 31 and 26 and a line 47 through the centers of the pivots 38 and 41 and that these two lines meet at a point 48. These links may, therefore, be termed converging links and the point 48 may be called their initial point of convergence. In the operated positions of the parts a line 51 has been drawn through the centers of the pivots 31 and 26 and a line 52 through the centers of the pivots 38 and 41 and said lines 51 and 52 meet at a point 53, which is the final point of convergence of the links. The line 46 inclines downward and toward the front of the machine and the line 47 upward and toward the front of the machine, the oint 48 at which these lines intersect standing a short distance in front of the pivot 26. When the parts are in normal position this point 48 is for the instant the theoretical center about which the lever 24 turns when the key first begins its downward stroke. For the first instant of the downward stroke of the key the lever 24 acts exactly as if it were pivoted on a fixed pivot at the point 48. Similarly at the last instant of the down stroke of the key the lever 24 is acting pre cisely as it would if it were pivoted at the point 53. During the down stroke of the key the theoretical center of the floating lever has moved from the point 48 to the point 53. In the initial position of this theoretical center the forward lever arm from the point 4-8 to the key 23 is long and the rear lever arm from the point 48 to the pivot 26 is com paratively short so that the key has a high leverage on the sub-lever. At the last part of the stroke the forward lever arm is meas ured from the key 23 to the point 53 and the rear lever arm from the point 53 to the point 26 so that said rear lever arm is quite long and the front lever arm comparatively short. During the down stroke of the key the key therefore has a rapidly decreasing leverage on the sub-lever. It will be per ceived that this change in leverage can be varied in the designing of the machine to a wide extent. initial leverage not so great as it is shown in the drawing, the link 40 will be set more nearly horizontal so as to throw the point 48 farther toward the front of the machine. The final location of the point 53 can be varied by varying the length of the link 40. How far the theoretical center moves toward the front during a key depression of a given extent, depends on the angle through which the link 40 turns. This angle will be less the longer the link, so that the rate at which the leverage decreases, can be lessened by making the link 40 longer. It will thus be seen that by changing the proportions of the parts, the key can be given any desired initial leverage on the sub-lever and the degree to which this leverage is increased during the down stroke of the key can be varied to any desired extent. I prefer so to construct the parts that the theoretical center is at all times somewhere near a horizontal line through the key. For this reason the line 47 initially has a downward inclination so that when the key is fully depressed it is nearly horizontal. By this construction the key moves almost directly downward.

Thetype action shown in Fig. 1 and the one shown nearest the operator in Fig. 3, is one of the middle type actions in which the lever arm 28 is shorter than some of the other sub-lever arms in the machine. Those sub-levers which operate the type bars near the ends of the segment, have longer arms 28 and suitable variation may be made in the other parts to compensate for this additional length of the arm 28. This compensation is shown here as being effected chiefly by making the forward arm 27 of the same sub-lever correspondingly long as shown in dotted lines in Fig. 3 at 27 Since this lever arm 27 is longer than the other lever arm 27 the corresponding pivot point 26 comes farther toward the front of the machine than the point marked 26. In order to preserve a uniform leverage throughout the system it is desirable that the point for this type action corresponding to the point 48 shall also be far- If it is desired to make the ther toward the front of the machine. To this end the link 40 connected with this end key lever is set at an angle more nearly horizontal than the link 40.

Some of the key levers extend farther toward the front of the machine than others. In most case shift typewriters, there are four rows of keys and that arrangement is shown in the present drawings. If the point 53 for one of the rear keys were as near the front of the machine as the corresponding point for one of the key levers having its key in the front row,

then the corresponding key 23 would have its leverage on the sublever diminished very much more than the key of the front row. For example, the point 58 in Fig. 3 is several times as far from the forward one of the keys 23 than it is from the rear one shown. It will be seen that it is desirable that the theoretical center does not move as far forward in the case of a key in the rear row as it does in the case of a key in the front row. This is brought about by making the link 40 longer where it is connected with the back keys than in the case of those links that are connected with the front keys. For a given extent of upward motion at the rear end of the key lever, this long link does not turn through as great an angle as the short link and con sequently the line corresponding to the line 52 would not be so nearly horizontal and the point corresponding to the point 53 would not be so near the front of the machine. It will be seen that it is thus possible to compensate both for the difference in the lengths of the sub-levers and also for the difference in the lengths of the key levers by suitable variations in the proportions of the parts. The lever arms 27 will be made of difierent len ths and the links 40 will be made of diifIrent lengths and set at different angles throughout the system. In order to allow for different lengths of links 40 and for setting these links at different angles, the lower ends of the branches 37 of the several key levers are broadened out in the manner shown in the drawings so that the pivot 38 can be put at any one of a number of different places depending on the length and inclination of the corresponding link.

The universal bar for operating the carriage escapement and the ribbon vibrator levers will move upward about the same distance, in factalmost exactly the same distance. I have therefore formed on the upper edge of each of said key levers near the rear end thereof a lug 54c for cooperation with a universal bar 55 which lies above the system of key levers and is arranged to be moved upward when any key is operated.

' This universal bar is here shown as forming part of a frame having side bars 56 which are pivoted at 57 on lugs or brackets rising from the cross bar 33. The frame also comprises a rear cross bar 58 having an arm 60 to which the link 16 is connected. The pivots 57 are between the ends of the bars 56 and the arm 60 moves downward when a key is depressed. This universal bar frame can also be connected in any suitable way with any suitable form of ribbon vibrator mechanism. The returning springs may be connected with this type action in any one of a number of different ways. I have here shown contractile springs 61 each having one end connected at 62 to a key lever and its other end connected to a cross bar 63 in the base of the machine. As these are contractile springs it is essential that they be connected with the key levers with proper reference to the location of the point 48 which represents the initial theoretical center of the lever. As these springs pull downward each spring should be connected to its key lever at a suitable distance to the rear of the point 48 for that particular lever. In practice the springs can all be arranged in a straight row at about the position shown in Fig. 1. The advantages resulting from the so-called accelerated motion of the type bar, are enhanced if this character of motion can be imparted to other of the connections in addition to the type bar. In the present instance it will be noted that not only the type bar but the link 30 and the sub-lever and the rear end of the key lever itself, all have this accelerated motion. The result is that the touch resulting from this form of type action is remarkably soft and pleasing. Not only do the several parts of the type action referred to, have an accelerated motion but the universal bar has also. This adds to'the quality of touch and it also adds to the efficiency of the universal bar in its operation of the escapement. When the key first starts on its up stroke the universal bar is moving at its highest rate of speed with reference to the key so that it very quickly moves the holding dog out of engagement with the escape ment wheel and allows the carriage to escape early in the return stroke of the key.

This floating key lever type action is capable of many modifications. In part of the discussion or explanation of it the lever arm 27 has been referred to as one of the links that supports and guides the key lever. It will, of course, be understood that it is not essential that this link be a part of the sub lever; but it can be a separate link and the key lever can be connected with the type bar in any manner desired. This link 27 is utilized as one arm of the sub-lever because that is the simpler and more direct construction and it is the construction that I prefer. Moreover, the acceleration could be obtained in substantially the same manner if the links were above the lever arms 27 instead of below them and inclined downward and toward the front instead of upward and toward the front. The arm 37 of the key lever is shown extending downward instead of upward in the present instance chiefly in order to avoid interference with the particular sort of sub-lever employed in the present instance. By suitably changing the disposition of the links, the rear end of the key lever can be made to move downward with an accelerated velocity, instead of up ward. In short, this scheme is capable of wide modification without departing from the principles hereinbefore explained and without parting from my invention.

What I claim as new and desire to secure by Letters Patent, is

1. In a typewriting machine, a linkage including a floating key lever having a key at its forward end and two converging links on which said lever is mounted, the point of convergence of said links being normally remote from said key and moving toward said key as said key is operated.

2. In a typewriting machine, a linkage including a floating key lever having a key at its forward end and two converging links on which said lever is mounted, the point of convergence of said links being normally remote from said key and moving toward said key as said key is operated, in combination with a type bar operatively connected with said linkage.

3. In a typewriting machine, the combination of a linkage including a floating key lever having a key at its forward end and two converging links supporting said lever at its rear part, said links being normally inclined to the horizontal and moving toward horizontal positions when the key is operated; and a type bar operatively connected With said linkage.

4. In a typewriting machine, the combination of a linkage including a floating key lever having a key at its forward end and two converging links supporting said lever at its rear part, the point of convergence of said links being normally a comparatively short distance in front of said links and moving when the key is operated toward the front; and a type bar operatively connected with said linkage.

5. In a typewriting machine, the combination of a floating key lever having a key at its forward end, a sub-lever one arm of which is pivoted to said floating lever, a link pivoted to said floating lever, and a type bar connected with said sub-lever, said sub-lever arm and said link constituting converging links on which said floating lever is mounted, and the point of convergence of said links moving when the key is operated so as to impart an accelerated motion to said sub-lever.

6. In a typewriting machine, the combination with a type bar, of a linkage for operating said type bar, said linkage comprising a key-operated float-ing lever hung on two non-parallel links, the point of convergence of said links moving, when the lever is operated, so as to impart an accel erated motion to the part of said floating lever that is connected with said type bar.

7. In a typewriting machine, the combination with a type bar, of a linkage for operating said type bar, said linkage comprising a key-operated floating lever hung on two non-parallel links and having a key at its forward end, the polnt of convergence of said links moving, when the key is operated, so as to impart an accelerated motion to the part of said floating lever that is connected with said type bar.

8. In a typewriting machine, the combination of a segmentally arranged series of front strike type bars, a series of sublevers having upstanding arms of different lengths connected with said type bars, a series of floating key levers, said sub-levers having arms pivoted to said key levers and said arms being of different lengths according tothe different lengths of the upstanding arms of the respective sub-levers, and links connected with said key levers, said links and the last mentioned arms of said sub-levers converging, and the several links set normally in different positions depending on the respective lengths of the associated suh-lever arms. T

9. In a typewriting machine, the combination of a series of type bars, a series of linkages each comprising a floating key lever hung on two converging links and said linkages connected with said type bars, said key levers having keys arranged in a plurality of transverse rows so that some of said key levers are longer than others, and the links of one of the series of links being of different lengths, the longer links being connected with the shorter key levers.

10. In a typewriting machine, the combination of a series of front-strike type bars, a series of sub-levers, a series of floating key levers, and a series of links, each of said type bars being connected with a sub-lever, each of said key levers being hung on a sub lever arm and on one of said links, said sublevers being of different lengths, said key levers being of different lengths and said links being of diflerent lengths, the longer links being connected with the shorter key levers.

11. In a typewriting machine, a linkage for operating a type bar, said linkage comi prising a floating lever, two converging links supporting said floating lever, means for operating said lever, and one of said links consisting of an arm of a lever arranged to be operated by said floating lever.

12. In a typewriting machine, a linkage for operating a type bar, said linkage comprising a floating lever, two converging links supporting said lever, and means for operating said lever, the point of convergence of said links being initially comparatively close to the part of said lever at which said links are connected thereto and moving away from said links during the operation of said lever.

13. In a typewriting machine, the combination of a series of linkages each including a floating key lever having a key at its forward end and two converging links sup-- porting said lever at its rear part, said links being normally inclined to the horizontal and moving toward horizontal positions when the key is operated; type bars operatively connected with said linkages, and a universal bar lying above said floating key levers and arranged to be moved upward with an accelerated motion when any key is operated.

Signed at the borough of Manhattan, city of New York, in the county of New York,

and State of New York, this 23rd day of March A. D. 1910.

ROBERT H. STROTHER.

Witnesses:

CHARLES E. SMITH, E. M. VVELLs. 

